Harnessing the free power of the wind to pump water
The need to fill up with water at regular intervals is an inconvenient necessity of steam locomotives, and it is apt to be an expensive one. The idea of harnessing the free power of the wind to pump water from one's own well is one that seems to have appealed to Colonel Stephens, who was always a man with an eye for a bargain.
Before looking at the windpumps used on the K&ESR and some of the Colonel's other railways, it will be useful to consider the technology available to him in the early 1900s. Traditional windmills had of course been around for centuries, but they were large and expensive structures, built and maintained by skilled craftsman and requiring constant attention. They were typically used to grind corn, but there were also quite a few pumping windmills. Most were for drainage but they were occasionally used for water supply, and the tower of one of these can still be seen near the motorway on the outskirts of Faversham, where it was built for the Corporation waterworks in about 1858 to supplement steam pumps.
As settlement spread across the plains and prairies of North America, farmers and ranchers needed a cheap, reliable way to tap underground water resources, and with typical Yankee ingenuity one Daniel Halladay designed a self-governing windmill (as it was called in America, though strictly speaking a wind pump or wind engine). This had a vane which automatically turned it to face changing wind directions, and a governor to regulate its speed automatically by pivoting the thin wooden blades which formed its wheel. Most importantly, it was a standard product that could be made in a factory. In partnership with a mill repairer, John Burnham, Halladay began to manufacture windmills in 1854, and was soon selling 'Halladay Standard' windmills by the thousand. Other companies and types appeared, for example the 'Eclipse' of 1867, and by the time of the Chicago International Exhibition of 1893, the various manufacturers were able to display a veritable forest of windmills. The first mass-produced windmills made largely of wood, but as the 19th century progressed, iron and steel were used more and more.
An important advance came when Halladay's US Wind Engine Company hired an engineer, Thomas O. Perry, who analysed the operation of windmills scientifically and developed a completely new and much more efficient design. The company was, however, reluctant to invest in re-tooling and rejected Perry's proposals. As a result, Perry went into partnership with a businessman, LaVerne Noyes, and they established the Aermotor Company in Chicago in 1888. At first users scoffed at what they dismissed as the 'mathematical windmill' and only a few units were sold in the first year. However, demand grew quickly and Aermotor soon came to dominate the market, once it was realised that an 8-foot diameter Aermotor could pump as much water as a 12-foot model of most other makes. The company is still in business, more than 120 years later.
The final technical development was the self-lubricating windmill, in which the gearing and other moving parts ran in an oil bath. Introduced about 1912 by the Elgin Wind Power and Pump Company, this feature was soon copied by almost every windmill manufacturer in North America. Before then, someone had to climb the tower once a week to grease the moving parts, but with the introduction of the oil bath, windmills could be left to pump unattended for anything up to a year at a time. The Aermotor Company brought out the self-oiling Model 502 in the USA in 1915. This proved not entirely satisfactory, and in 1916 it was replaced by the Model 602, which remained in production until 1933. Many parts of the Model 602 were interchangeable with its predecessor, the Pumping Aermotor, and following a successful campaign by the company to sell replacement self-oiling heads, relatively few of the earlier models were left in their original condition in America.
Rural electrification began to reduce the need for pumping windmills in their country of origin in the 1930s, but some of the estimated six and a half million units sold in the USA are still working, and indeed both new and reconditioned wind pumps are readily available today.
American railroads were quick to adopt windpumps in suitable terrain, and this included important companies such as the Union Pacific and the Southern Pacific. Watering points were set up every thirty miles or so in desert country, with storage tanks and windpumps to raise water from wells. Some models were designed specifically for this duty, the 'Railroad Eclipse' being one.
American-style windpumps were never as ubiquitous in Britain as they were in North America and in other countries with comparable conditions, such as Australia, Argentina and South Africa. However, they did become a reasonably common sight, particularly in flatter, drier areas. The Royal Agricultural Society of England organised wind engine trials in 1903, and awarded medals to favoured models. Among British firms, Duke & Ockendon ('Dando') of Littlehampton (which is still in business as a manufacturer of drilling equipment) offered a range of wind pumps, often on more than usually elaborate steel towers. Some were supplied to British railway companies, including the London & South Western (for example at Gillingham, Dorset, and Bentley, Hampshire) and the London, Brighton & South Coast (for example at Christ's Hospital and Ford). The windpump at Ford was accompanied by a cylindrical water tank of classic American appearance, and survived into the 1950s, when most of the trains on the line had been electric for years. Another British manufacturer was John Wallis Titt of Warminster, who is known to have supplied windpumps to the Midland, Great Western and London & South Western Railways. L&SWR locations included Amesbury Junction, and a couple of stations on the Basingstoke and Alton Light Railway, including Cliddesden (the windpump can be seen briefly in the Will Hay film, 'O, Mr Porter'). The Basingstoke & Alton examples seem to have been used to supply water to the stations and railway cottages, rather than for locomotive purposes.
Colonel Stephens did not patronise British manufacturers, but purchased American Aermotor windpumps. These had a good reputation for quality and reliability, while mass production had reduced prices to as little as 25 US dollars by the early 1900s. Definite information is lacking, but from records in the archives at Tenterden it seems likely that the equipment was purchased through the Aermotor Company's English agent, Lloyd, Lawrence & Co. of Worship Street, London EC. Lloyd, Lawrence displayed windpumps at several Royal Agricultural Society shows, including the one at Maidstone in 1899, and it is possible that Colonel Stephens became aware of the potential of the windpump as a result of a visit to the show.
A typical Aermotor windpump has three principal components. On the top is the wheel of curved metal blades, mounted slightly off-centre, so that the pressure of the wind tends to turn it out of the wind. It is returned to face into the wind by a tail vane, which is connected to the wheel support by a governor spring, so that the angle of the wheel to the wind varies according to the strength of the wind. A brake holds the wheel stationary when required. The rotation of the wheel is converted into an up-and-down movement of a vertical rod by reduction gearing and a pitman. The reduction gearing allows the wheel to turn even in a light wind. The supporting tower is typically assembled from galvanized steel angle, rather like an electricity pylon. Loop steps are often fixed to one of the corner posts, allowing for a rather precarious ascent to a platform near the top of the tower to lubricate or repair the mechanism. Beneath the tower is a well, often quite shallow, containing a cylinder and a plunger, both fitted with check valves. As the plunger is moved up and down in the cylinder by the sucker rod, water is forced from the well into the cylinder, then from the cylinder into the plunger, and finally into a drop tube which takes it out of the well and into a storage tank. The output obviously varies greatly according to the size of the wind wheel, the difference in level through which the water had to be pumped, and wind conditions. However, under favourable conditions, windpumps like those used on the K&ESR might be expected to deliver up to about 3000 gallons a day.
Of the Colonel Stephens railways, the Kent & East Sussex was the largest user of windpumps, with three examples, at Robertsbridge, Tenterden Town and Headcorn. They were all Pumping Aermotors, possibly the 1899 model, and it is a reasonable guess that they were all put in at about the time the Tenterden Town to Headcorn line was opened in 1905. The East Kent and the Shropshire & Montgomeryshire had one each, and there was also one on the Sheppey Light, although this was installed by the South Eastern & Chatham Railway, when the Colonel's connection with the line had ceased. Curiously, neither the Selsey Tramway nor the Weston, Clevedon & Portishead seems to have employed windpumps, although on the face of it the flat landscape which surrounded the railways would seem to favour them. Details of individual windpumps are as follows.
Kent & East Sussex Light Railway
A windpump and a rectangular water tank on timber supports were located on the north side of the line, just west of North Bridge Street level crossing. There is some doubt as to whether this pump was actually used, and, certainly, an early spare parts list in the Colonel Stephens Museum archives is labelled as referring to the Tenterden and Headcorn windpumps only. This was probably because K&ESR engines were able to take water at Robertsbridge Junction where a large water tank and a double-sided water crane of typical South Eastern Railway design were located between the down main line and the down siding. In 1906 the K&ESR agreed with the South Eastern & Chatham Railway to take water at Robertsbridge for a payment of £15 per year, and the agreement was renewed at a higher cost in 1922. By the early 1950s, only the tower of the Robertsbridge windpump remained.
8-foot Aermotor windpump was provided on the east side of the line some distance north of the station. It was quite soon moved to a point near the Headcorn end of the former second platform. The date of the move is uncertain, but Trott and Vener, well diggers of Robertsbridge, were paid for work for the K&ESR in January 1907, and it is possible that this was the excavation of the new and evidently shallow well at Tenterden. The windpump presumably supplied the balloon water tower at the opposite end of the second platform, near where the signal box now stands. The pump survived intact until the early 1950s, and the steel tower remained a little longer.
An Aermotor windpump and a rectangular steel tank on timber supports were installed a little way out of the station by the end of the headshunt. They were certainly there by 1910 and, as explained above, probably earlier. They lasted into the 1950s.
East Kent Light Railway
A Model 602 self-oiling Aermotor windpump fed a rectangular water tank on timber supports at the end of the platform. It was on an Aermotor steel tower with corner loop steps and a wide base to straddle what was probably a hand-dug well. According to British Geological Survey records, the well was only about 10 feet deep. The self-oiling Aermotor was on the market in Britain from about 1917, so this example may date from soon after public opening of as far as Wingham in 1916. The windpump (though not the tank) was removed some time after 1947.
Shropshire & Montgomeryshire Light Railway
A Pumping Aermotor supplied a rectangular water tank on brick pillars near the engine shed. Again, the base of the steel tower was quite wide, probably to straddle a hand-dug well. It seems likely that the windpump was installed shortly after the line opened in 1911. The wheel and mechanism were removed between 1935 and 1938, though the tower remained, presumably to disappear during scrap drives and military occupation in the Second World War. As a sidelight on the water supply arrangements of the Shropshire & Montgomeryshire, in 1930 W.H. Austen gave orders that no engine was to take water at Shrewsbury unless absolutely necessary, as the company had to pay for water there, on measurement. The water tank at the Abbey Foregate station is the same one that was in use at Wittersham Road on the K&ESR and is now in store.
Sheppey Light Railway
The South Eastern & Chatham Railway, which worked the Sheppey Light from its opening and purchased it in 1905, signed a contract with J. Warner & Sons in 1904 to construct a well and windpump at the Leysdown terminus to supply a large rectangular tank on a brick base. This arose from the introduction of Kitson steam railmotors for passenger trains and the secondhand 'Terrier' known to the men as 'Little Titch' for goods. Both had a much smaller water capacity than the rebuilt 'Sondes' class tank engines which were used when the line first opened. According to a (probably apocryphal) story, while the well was being bored, a harder stratum of rock was encountered and the drill was diverted sideways. The workmen are supposed to have realised this only when it emerged from the ground some distance away. Be this as it may, when work was completed in 1905 the final bill was twice the original estimate of £625. According to British Geological Survey records, the well was about 55 feet deep. No details of the windpump have yet emerged, and I have not seen a clear photograph of it. However, the depth of the well implies a larger unit than those installed by the Colonel if an adequate delivery rate was to be achieved. The water supply at Leysdown seems to have continued to present problems, as photographs taken in the 1920s show the usual 2-coach motor train set converted from the carriage portions of railmotors being hauled by elderly tender engines. Presumably the windpump was eventually superseded by a mains water supply from the Leysdown pumping station, which had a borehole some 440 feet deep, drilled in 1918.
The windpumps of the K&ESR and the East Kent have been described by authors of books on those railways as an unreliable source of water. The Pumping Aermotor designs used on the K&ESR and the Shropshire & Montgomeryshire needed someone to climb the tower every week or so to grease the mechanism, and of course there was always a risk of this unpopular job being overlooked, leading to undue wear. Given proper lubrication, however, the Aermotor was regarded as a robust piece of machinery that required little other attention. It is also possible that the rather shallow wells that seem to have been used may have been liable to run dry in periods of drought. None the less, some of the Colonel's Aermotor windpumps gave service for several decades and undoubtedly saved on bills for mains water supply.
American-style windpumps are now quite a rarity in Britain, but one can still be seen from the K&ESR in a field on the west side of the line a little way on the Wittersham Road side of Rolvenden. This is a smaller design with only four blades, rather than the multi-bladed wind wheels used on the windpumps described above. Two Duke & Ockenden windpumps are on display in the south of England, at the Surrey Rural Life Centre at Tilford, near Farnham, and at the Chalkpits Museum, Amberley, West Sussex. I do not know of a preserved Aermotor windmill in this country, and should the resources be available in the future it would be interesting to try to acquire one for re-erection on the K&ESR.
The surviving minute books and other official records of the Colonel Stephens railways make no mention of the installation of windpumps, and many of the details above have been gleaned from the study of photographs. In this context, I should particularly like to thank Dr T Lindsay Baker, Director of the Texas Heritage Museum and author of the standard work on the subject, 'A field guide to American windmills' (University of Oklahoma Press, 1985), for his invaluable assistance. Mr J Kenneth Major of Reading has also provided many interesting details of the manufacture and sale of windpumps in the United Kingdom.
This article by Tom Burnham appeared in the Summer 2001 edition of The Tenterden Terrier